BUG: If CSS compression has been enabled, the module specific CSS override files in /css/modules/yaml.*.css are missing. The parameters of drupal_add_css() inside the function _yaml_add_css_modules() have missed to upgrade from D6 to D7. Replaced D6 'theme' to D7 array('group' => CSS_THEME).

Integrated YAML-Grids as ctools plugins into the theme. You no longer need to copy these layouts manually to the panels/plugins/layouts folder. If Panels module may need an update you will no longer loose the layouts. By this change the layout previews in admin theme are now displayed properly in standard compliant browsers.

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Added alias .node-teaser h2 to h3 for reduced teaser title size. Should be changed to node-teaser.tpl.php for semantical correctness (TODO)

HTML5 Tools: Makes the site HTML5 compliant. Core RDF module may need to be disabled to remove all validator complains.

404 Navigation: On 404 Not Found error pages, Drupal will skip rendering of all the navigation links of your website for performance reasons and makes your maintenance template far useless. This module solves this issue.